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1.
Eur J Cancer Care (Engl) ; 24(6): 812-7, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26094701

RESUMEN

This pilot study investigated feasibility and preliminary efficacy of a high-intensity functional training (HIFT) group-exercise programme among adult cancer survivors within 5 years of last cancer treatment. Eight participants were assigned to a 5-week, 3 days/week HIFT intervention with four testing sessions and 12 workouts along with mobility and stretching exercises. Feasibility was assessed by initiation, adherence, and acceptability. Efficacy was determined by changes from baseline to post-test in health-related quality of life, body composition and functional movement. The recruitment rate was 80% and the adherence rate was 75%. Significant improvements were found for emotional functioning (P = 0.042) and body composition (lean mass +3.8 ± 2.1 kg, P = 0.008; fat mass -3.3 ± 1.0 kg, P = 0.001; body fat percentage -4.7 ± 1.2%, P < 0.001). Participants also significantly improved on five of seven functional movements: balance (P = 0.032), carrying a weighted object (P = 0.004), lower body strength and power (P = 0.009), aerobic capacity and endurance (P = 0.039), and perceived difficulty for flexibility (P = 0.012). Five weeks of HIFT training was well-received and feasible for most cancer survivors, and effective for improving emotional functioning, body composition and functional movement.


Asunto(s)
Composición Corporal , Terapia por Ejercicio/métodos , Fuerza Muscular , Neoplasias/rehabilitación , Sobrevivientes , Tejido Adiposo , Estudios de Factibilidad , Femenino , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Resistencia Física , Proyectos Piloto , Equilibrio Postural , Calidad de Vida , Resultado del Tratamiento
2.
Animals (Basel) ; 12(23)2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36496857

RESUMEN

Angus and Red Angus-based yearling heifers (n = 40) and lactating cows (n = 51) were each used in a complete randomized design and stratified by weight and body condition score to one of two treatments: (1) pressed supplement block containing rumen undegradable protein (RUP) and (2) pressed supplement block containing rumen degradable protein (RDP). Heifer and cow supplement intake displayed (p < 0.01) a treatment × period interaction. The RUP heifers and RDP cows consumed more in Period 2 than Period 1, whereas RDP heifers and RUP cows consumed more in Period 1 than Period 2, respectively. Intake rate demonstrated (p < 0.01) a treatment effect for heifers, with RUP consuming supplement faster than the RDP treatment. Intake rate for cows demonstrated (p < 0.01) a treatment × period interaction with RUP cows in Period 1 having faster intakes than Period 2, and RDP cows having the inverse. Cow intake variation displayed (p < 0.01) a treatment × period interaction with RUP cows having more variation in Period 2, while RDP cows had less variation in intake in Period 2. In conclusion, RDP and RUP impacted intake behavior of cows and heifers but had minimal impacts on performance.

3.
R Soc Open Sci ; 6(12): 170501, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31903193

RESUMEN

Sleep aids the consolidation of recently acquired memories. Evidence strongly indicates that sleep yields substantial improvements on recognition memory tasks relative to an equivalent period of wake. Despite the known benefits that sleep has on memory, researchers have not yet investigated the impact of sleep on eyewitness identifications. Eyewitnesses to crimes are often presented with a line-up (which is a type of recognition memory test) that contains the suspect (who is innocent or guilty) and fillers (who are known to be innocent). Sleep may enhance the ability to identify the guilty suspect and not identify the innocent suspect (i.e. discriminability). Sleep may also impact reliability (i.e. the likelihood that the identified suspect is guilty). In the current study, we manipulated the presence or the absence of sleep in a forensically relevant memory task. Participants witnessed a video of a mock crime, made an identification or rejected the line-up, and rated their confidence. Critically, some participants slept between witnessing the crime and making a line-up decision, while others remained awake. The prediction that participants in the sleep condition would have greater discriminability compared to participants in the wake condition was not supported. There were also no differences in reliability.

4.
Ann N Y Acad Sci ; 370: 366-77, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7023321

RESUMEN

1. The protein concentration dependence observed in the calcium binding to fragment 1 indicates that calcium-mediated dimerization is responsible for the cooperative calcium binding behavior usually observed. "Unusual" fragment 1, which exhibits negative cooperativity (the type of binding behavior expected for ions interacting with a charged protein) at high concentration, also exhibit altered self-association behavior. 2. The calcium-induced spectral perturbations that are observed by fluorescence and ultraviolet difference spectroscopy are influenced by calcium-mediated dimerization. Similar spectral perturbations may also be induced by other divalent, trivalent, and monovalent ions, as well as changes in pH. Because this is a multi-site system, only limited interpretation of the spectral data is possible without calcium binding data. 3. Although strong side chain CD signals make estimation of fragment 1 secondary structure ambiguous, the CD data do indicate small changes in structure during calcium binding. Similar changes are observed upon addition of monovalent ions at high concentration or after lowering the pH. No coupling between changes in conformation and the cooperative calcium binding behavior has yet been observed to exist.


Asunto(s)
Calcio/metabolismo , Factor X/metabolismo , Fragmentos de Péptidos , Precursores de Proteínas/metabolismo , Protrombina/metabolismo , Protrombina/farmacología , Sitios de Unión/efectos de la radiación , Factor Xa , Humanos , Concentración de Iones de Hidrógeno , Concentración Osmolar , Conformación Proteica , Espectrofotometría Ultravioleta , Temperatura
5.
Lipids ; 10(7): 437-40, 1975 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-167262

RESUMEN

The hypocholesteremic compound, 3beta-(beta-dimethylaminoethoxy)-androst-5-en-17-one was earlier shown to inhibit the synthesis of tetrahymanol and two undentified lipids. It now has been demonstrated that one of the unidentified compounds is diplopterol.


Asunto(s)
Androstenos/farmacología , Anticolesterolemiantes/farmacología , Esteroles/biosíntesis , Tetrahymena pyriformis/metabolismo , 17-Cetosteroides/farmacología , Animales , Cromatografía , Cromatografía de Gases , Cromatografía en Capa Delgada , Éteres de Etila/farmacología , Espectrometría de Masas , Dióxido de Silicio , Tetrahymena pyriformis/efectos de los fármacos
8.
Biochemistry ; 19(6): 1161-7, 1980 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-6245680

RESUMEN

Vitamin K dependent carboxylation of an exogenous peptide substrate and endogenous protein substrates, vitamin K epoxidation, and reduction of vitamin K epoxide were measured in subcellular fractions from rat liver. The rough microsomal fraction was highly enriched in all four activities; lower levels were found in smooth microsomes. Mitochondria, nuclei, and cytosol had negligible activities. The addition of 0.2% Triton X-100 to intact microsomes resulted in a 10-20-fold stimulation in carboxylation of a peptide substrate. This marked latency suggests that the active site of the carboxylase may be accessible only from the lumen of the microsomal membrane. A lumen-facing orientation of the carboxylase was also supported by its inaccessibility to trypsin in intact microsomes contrasted with marked inhibition by trypsin in detergent-permeabilized microsomes. Vitamin K epoxidase and epoxide reductase activities were also inhibited by trypsin much more effectively in permeabilized than in intact microsomes, although some degree of exposure at the cytosolic surface was also indicated. These data suggest that carboxylation is an early event in prothrombin synthesis occurring primarily on the lumen side of the rough endoplasmic reticulum membrane. The location of the vitamin K epoxidation-reduction cycle enzymes is consistent with their possible role in the carboxylation reaction.


Asunto(s)
Ligasas de Carbono-Carbono , Ligasas/metabolismo , Hígado/enzimología , Deficiencia de Vitamina D/enzimología , Vitamina K/metabolismo , Animales , Glucosa-6-Fosfatasa/análisis , Masculino , Octoxinol , Polietilenglicoles/farmacología , Ratas , Fracciones Subcelulares/enzimología , Tripsina/farmacología
9.
J Am Acad Dermatol ; 22(5 Pt 2): 956-9, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2335589

RESUMEN

Zygomycosis, an invasive fungal infection, is usually seen in persons with diabetes, particularly in those with diabetic ketoacidosis. The infection most frequently occurs in the rhinocerebral region and rapidly spreads, causing a swift demise. Rarely, the infection is confined to the cutaneous tissues. We describe a 31-year-old man seropositive for human T lymphotropic virus type I who had diabetic ketoacidosis with zygomycosis confined to the right arm. The lesion was presumed initially to be a bacterial infection but did not respond to conventional antimicrobial therapy. The arm lesion was cultured, and Rhizopus arrhizus was isolated. The patient responded well to a combination of amphotericin B and extensive surgical debridements. Our case emphasizes the importance of maintaining a high index of suspicion of cutaneous zygomycotic infections in the impaired host, especially of those in patients with diabetes, who do not respond to initial antimicrobial treatment.


Asunto(s)
Diabetes Mellitus Tipo 1/complicaciones , Infecciones por HTLV-I/complicaciones , Mucormicosis/complicaciones , Adulto , Terapia Combinada , Humanos , Masculino , Mucormicosis/patología , Mucormicosis/terapia , Necrosis , Rhizopus , Piel/patología
10.
J Biol Chem ; 265(35): 22044-55, 1990 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-2254347

RESUMEN

Two pathways are possible during the proteolytic formation of alpha-thrombin (alpha-IIa) from prothrombin (II) or prethrombin 1 (P1). One of the pathways, with prethrombin 2 or prethrombin 2 associated with fragment 2 (P2F2) as intermediates, has long been known to exist when activation is catalyzed by Factor Xa (Xa) alone. The second pathway, with meizothrombin or meizothrombin (des fragment 1) (MzIIa(-F1)) as intermediate, has been shown to exist when Factor Va and phospholipids are present with Xa. Until now, MzIIa(-F1) has not been detected in reactions catalyzed by Xa alone. In this study, we demonstrate that P1 activation by Xa alone occurs via both pathways, and we provide rate constants and kinetic equations for calculating the relative contributions of each of the pathways to the formation of alpha-IIa by Xa. Investigation of the initial rates of proteolytic cleavage of P2F2 and P1 by Xa alone indicated first-order dependence on substrate concentration with no evidence of saturation of Xa with either substrate at concentrations as high as 200 microM. Apparent second-order rate constants (kc/Km) of 113 +/- 9 M-1 s-1 for the formation of thrombin from P2F2 and 1,410 +/- 19 M-1 s-1 for the disappearance of P1 were determined at pH 7.5, 25 degrees C, 10 mM CaCl2, 0.15 M ionic strength. A two-step sequential first-order pathway employing these rate constants for thrombin activity production from P1 via P2F2 could not, however, account for the quantity of thrombin that was produced during the early stages of P1 activation. Addition of a parallel first-order reaction to produce thrombin activity from P1 independently of P2F2, tentatively identified as the formation of MzIIa(-F1), yielded progress curves in quantitative agreement with the experimental data. kc/Km for the parallel reaction was estimated to be 98 +/- 10 M-1 s-1. Independent determination of the second-order rate constant for the cleavage of isolated MzIIa (-F1), 15,000 +/- 420 M-1 s-1, indicated that MzIIa(-F1) could meet the kinetic requirements for an intermediate in the parallel activation pathway. The transient formation of MzIIa (-F1), as well as the generation of alpha-IIa, was directly demonstrated during activation of P1 by active site-affinity labeling of the reaction products with a biotin derivative of D-Phe-Pro-Arg chloromethyl ketone and visualization by semiquantitative Western blotting.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Activación Enzimática , Factor Xa/metabolismo , Protrombina/metabolismo , Animales , Western Blotting , Calcio/metabolismo , Bovinos , Cinética
11.
Proc Soc Exp Biol Med ; 148(1): 140-4, 1975 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1129252

RESUMEN

Abnormal, biologically inactive forms of prothrombin have previously been shown to appear in the plasma of cows or humans given coumarin anticoagulants. We have previously shown that a protein with similar properties increases in the liver of rats given these vitamin K antagonists, and have postulated that this protein represents the liver precursor to plasma prothrombin. Eight species, rats, mice, guinea pigs, hamsters, rabbits, calves, dogs, and chickens, have now been surveyed for both plasma abnormal prothrombin and liver precursor activity. Large amounts of plasma abnormal prothrombin were found in the bovine, substantial amounts were seen in the chick, and small amounts in rat and mouse plasma. With the exception of the bovine, all anticoagulant treated animals showed elevated levels of liver precursor activity in microsomal preparations. The relationship of these observations to the mechanism of action of vitamin K is discussed.


Asunto(s)
Microsomas Hepáticos/metabolismo , Precursores de Proteínas/metabolismo , Protrombina/metabolismo , Animales , Bovinos , Pollos , Cricetinae , Perros , Femenino , Cobayas , Conejos , Ratas , Factores de Tiempo , Warfarina/farmacología
12.
Fed Proc ; 37(12): 2605-9, 1978 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-700169

RESUMEN

It has been postulated that the liver microsomal conversion of vitamin K hydroquinone to its 2,3-epoxide (epoxidase activity) is coupled in some obligatory fashion to the vitamin K-dependent carboxylation (carboxylase activity) event also occurring in microsomes. This hypothesis is supported by the observations that the requirements for the two reactions are similar and that conditions that promote increased carboxylation increase the epoxidase activity. It has now been shown that both of these reactions are localized in the rough microsomal fraction of a cellular homogenate, and that both activities appear to be located on the luminal rather than the outer surface of microsomal membrane vesicles. The epoxidase activity has been found to be enriched as the microsomal carboxylase activity is fractionated, and a microsomal inhibitor of the carboxylase activity had been shown to also inhibit the epoxidase activity. The enzyme glutathione peroxidase inhibits both of these activities, suggesting that a hydroperoxide of the vitamin might be an intermediate for both reactions. The organic hydroperoxide t-butyl-OOH has also been shown to have weak vitamin K-like activity in an in vitro system. These data strengthen the hypothesis that these two reactions are related, perhaps through a common intermediate, but do not provide a definite molecular role for this interrelationship.


Asunto(s)
Microsomas Hepáticos/metabolismo , Vitamina K/fisiología , Ácido 1-Carboxiglutámico/metabolismo , Animales , Dióxido de Carbono/metabolismo , Carboxiliasas/metabolismo , Compuestos Epoxi , Glutamatos/metabolismo , Cinética , Microsomas Hepáticos/enzimología , Peroxidasas/metabolismo , Protrombina/metabolismo , Ratas , Vitamina K/análogos & derivados
13.
J Lipid Res ; 37(10): 2088-97, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8906586

RESUMEN

In chick embryo hepatocytes, triiodothyronine (T3) causes a 30- to 40-fold increase in malic enzyme activity when added between 1 and 3 days, but has no effect when added between 5 and 7 days in culture. This transcription-mediated decline in T3 responsiveness is partially reversed by corticosterone (Roncero, C. and A. G. Goodridge, 1992. Arch. Biochem. Biophys. 295: 258-267). Clofibrate also reversed the decline in responsiveness to T3, and did so in the absence of an increase in binding of T3 to nuclear receptors. The effects of clofibrate and corticosterone were additive, suggesting different mechanisms. The responsiveness of a gene to a specific agent depends on specific regulatory sequences of DNA in that gene. When 5.8 kb of the 5'-flanking DNA of the malic enzyme gene was linked to the chloramphenicol acetyltransferase (CAT) gene and transfected into hepatocytes, T3 stimulated CAT activity. Responsiveness of CAT activity to T3 decreased with time, and this decrease was partially reversed by clofibrate. The T3 responses of cells transfected with various chimeric DNAs that contained T3 response elements (T3REs) of the malic enzyme gene or synthetic consensus T3REs also were increased by clofibrate. The results suggest that clofibrate regulates expression of a metabolite or a protein factor which, in turn, influences function of the T3 receptor.


Asunto(s)
Clofibrato/farmacología , Hipolipemiantes/farmacología , Hígado/enzimología , Malato Deshidrogenasa/genética , Triyodotironina/farmacología , Animales , Secuencia de Bases , Células Cultivadas , Embrión de Pollo , Secuencia de Consenso , ADN/química , ADN/efectos de los fármacos , ADN/metabolismo , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/embriología , Secuencias Reguladoras de Ácidos Nucleicos , Transcripción Genética/efectos de los fármacos
14.
Proc Natl Acad Sci U S A ; 78(8): 4772-6, 1981 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6946425

RESUMEN

The mechanisms by which blood levels of prothrombin (PT) are regulated in the vitamin K-sufficient state are unknown. We have studied PT synthesis by Reuber H-35 rat hepatoma cells exposed to vitamin K and [3H]leucine in serum-free cultures. Administration to the culture system of exogenous bovine PT and rat PT was characterized by increases in endogenous PT synthesis and secretion of 2- and 3-fold, respectively. This induction required endogenous proteolytic degradation of PT. Studies conducted with bovine PT fragment 1 (residues 1-156) demonstrated up to 5-fold increases in PT synthesis. This induction was dose dependent and saturable. Addition of bovine PT chymotryptic fragments to the cells indicated that the NH2-terminal peptide of prothrombin (residues 1-42) contained the requisite structural elements for the induction. Peptide-bound gamma-carboxyglutamate residues were required for the observed stimulation of PT synthesis. These results suggest that PT synthesis might be regulated physiologically by the products formed during its normal turnover and consumption during blood coagulation.


Asunto(s)
Neoplasias Hepáticas Experimentales/metabolismo , Fragmentos de Péptidos/farmacología , Protrombina/biosíntesis , Secuencia de Aminoácidos , Animales , Células Cultivadas , Relación Dosis-Respuesta a Droga , Inducción Enzimática/efectos de los fármacos , Hígado/metabolismo , Ratas , Relación Estructura-Actividad
15.
Ann Oncol ; 11(9): 1141-6, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11061609

RESUMEN

BACKGROUND: Patients with resistant diffuse aggressive non-Hodgkin's lymphoma (DA-NHL) have a poor prognosis. Studies have suggested infusional therapy may be beneficial. PATIENTS AND METHODS: This trial used an infusional regimen called I-CHOPE in resistant patients who had previously received only bolus CHOPE or CHOP regimen. Resistance was defined as: a) primary refractory disease, b) progression on therapy, c) partial response, d) complete remission lasting less than one year. Eligibility criteria included a diagnosis of DA-NHL (IWF E-H), no prior irradiation and adequate organ function. RESULTS: Thirty-seven patients were entered and twenty-nine were eligible. Reasons for ineligibility were incorrect histology (5) and other (3). The median age was 57 years (range 29-81) with 21 males. The performance status scores were: 0 (12 patients); 1 (9 patients); 2 (8 patients). Prior therapy consisted of standard CHOP (26 patients), bolus CHOPE (2 patients), high dose CHOP (1 patient). Therapy consisted of a 120 hour continuous intravenous infusion of doxorubicin 10 mg/m2/day, vincristine 0.28 mg/m2/day (maximum 0.4 mg/day), and etoposide 48 mg/m2/day. Cyclophosphamide 750 mg/m2 was given as an i.v. bolus day 6 and prednisone was given at 100 mg/day p.o. on days 1-5. G-CSF was allowed for myelosuppression. The overall response rate was 48% (CR 17%; PR 31%). Freedom from progression was 24% at six months and 8% at one year. Survival was 69% at six months and 40% at one year. In an exploratory analysis a prior CR or PR predicted response to I-CHOPE. Twelve of sixteen patients who had a CR/PR on previous therapy responded while two of thirteen who had no prior response, responded to I-CHOPE (P = 0.003). The toxicity was tolerable with grade 3-4 hematologic toxicity being leucopenia 94% and thrombocytopenia 41%. The grade 3-4 non-hematologic toxicities were infection in 28%, phlebitis in 11%, and stomatitis in 15%. CONCLUSIONS: I-CHOPE can induce responses in this group of patients with a poor prognosis, but most were seen in those who had previously had a response to bolus chemotherapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Etopósido/administración & dosificación , Linfoma no Hodgkin/tratamiento farmacológico , Prednisona/administración & dosificación , Vincristina/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Resistencia a Antineoplásicos , Femenino , Humanos , Infusiones Intravenosas , Linfoma no Hodgkin/mortalidad , Linfoma no Hodgkin/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Recurrencia , Análisis de Supervivencia , Resultado del Tratamiento
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